HIGH STRENGTH SUPERALLOY PARTS WITH GRADUAL CHANGE CHARACTERISTICS

摘要

A novel heat treatment of a disk for a jet engine is provided. A temperature gradient is established on the disk to heat the inner portions to a temperature at which a subsolvus anneal takes place and to heat the outer portions to a temperature where a supersolvus anneal takes place. A reverse gradient is established from the inner portions of the disk during cooling after the anneal to cool the inner portions of the disk more rapidly than the outer portions so as to impart high tensile and fatigue strength to the inner portions and high temperature rupture life and crack growth resistance to the outer portions. A novel disk results.